Rotary cutting heads having replaceable cutting blade inserts are well known as exemplified, for example, by U.S. Pat. No. 5,647,699. Additionally, helical rotary cutter heads with replaceable carbide blade inserts are also well known as shown, for example, in U.S. Pat. No. 3,725,988 to Sunderman et al., assigned to Sonnet Tool and Manufacturing Company. These types of rotary cutter heads incorporated carbide material which is known for excellent hardness characteristics, long life and durability.
For many years, Sonnet Tool and Manufacturing Company had provided helical carbide cutting tools and replaceable carbide cutting blades, which have been traditionally sold under the HELICARB trademark. Recently, the present assignee of the instant invention acquired Sonnet Tool and Manufacturing Company, and has continued to provide similar products under the HELICARB trademark. While the HELICARB products have satisfied a significant industry need, the inventors of the present invention have realized certain long existing drawbacks of helical cutting tools and particularly carbide helical cutting tools, to which the improvements of the present invention are directed.